Air conditioning apparatus



Patented Feb. 22, 1944 4 Es PATENT FFICE AIR, CONDITIONING APPARATUS Edward R. Wolfert, Springfield, to Westinghouse Electric &

Company, of Pennsylvania Mass., assignor Manufacturing East Pittsburgh, Pa., a corporation Application June 28, 1941, Serial No. 400,162 6 Claims. (01. 62-6) My invention relates to air conditioning apparatus, more particularly to a reversible cycle refrigerating system for either heating or cooling air for comfort, and it has for an object to protil lide improved apparatus of the character set A further object is to provide a reversible cycle refrigerating system that may be manufactured at reduced cost.

Another object is to provide a reversible cycle refrigerating system subject 'to minimum possibility of leakage of refrigerant.

Another object is to provide electrically-energized reversing means so that the cycle of operation may be reversed by merely actuating an electric switch.

In accordance with my invention, I provide a fluid-tight casing enclosing the compressor and the motor which drives the compressor. I dispose the reversing valve, that is, the valve structure which reverses the direction of flow through the condenser and evaporator elements, within the fluid-tight casing, thereby simplifying and reducing the cost of the apparatus, and also minimizing the possibility of refrigerant leakage.

In the preferred embodiment of my invention, I provide a reversible motor for driving the compressor, and I provide means for actuating the reversing valve by and in accordance with the direction of rotation of the motor-compressor unit.

These and other objects are effected by my invention as will be apparent from the following description and claims taken in connection with the accompanying drawing forming a part of this application, in which:

vFig. 1 is a diagrammatic view of a reversible cycle refngeratmg system in accordance with my invention;

Fig. 2 is a sectional view of a reversing valve which may be employed; and

Fig. 3 is a wiring diagramof a modified form of control.

Referring to the drawing in detail, I show a reversible cycle refrigerating system including two heat exchangers l0 and II which may be of the conventional cross-finned serpentine coil type. the coil l0 and delivering the same to the enclosure to be air conditioned. The coil Ill serves as the evaporator'during the cooling cycle and as the condenser during the heating cycle. Provision is also made for conveying outside air over the coil II and for discharging the same to outdoors or other place exterior of the enclosure.

Provision is made for conveying air over from the interior arrangement of the accumulator The coil I l serves as the condenser during the cooling cycle and as the evaporator during the heating cycle. The runs or tubes of each coil are preferably connected to provide a refrigerant path extending from the top through the successively lower adjacent runs to the bottom of the coil, so that, when the coil is serving as the condenser, the condensed refrigerant flows by gravity to the bottom of the coil.

A capillary tube H, of considerable length and restricted bore, and which is constantly open and provides constant restriction to flow, is connected between the lower ends of the two coils. It serves as the expansion device during both the heating and the cooling cycle.

The refrigerating system further includes a motor-compressor unit l3, which comprises a compressor. l4 and a motor I5 directly connected to the compressor for driving the same. The compressor and the motor are enclosed within a hermetically-sealed orfluid-tight casing l6, which contains refrigerant gas at suction pressure. The compressor draws refrigerant gas of the casing It, the gas being drawn through the motor for the purpose of cooling the same and then conveyed through a conduit II to the compressor. The compressed gas is conveyed from the compressor through a discharge conduit l8 to a reversing valve l9. A

reservoir or accumulator 2| is provided in the path of the suction gas to separate out and to retain liquid refrigerant from the suction gas returning from the evaporator. Respecting the in the system, reference is made to my copending application Serial No. 400,161, filed June 28, 1941, and Serial No. 518,513, filed January 17, 1944. The accumulator 2| is disposed within the casing l6 and its inlet is connected to the reversing valve I 9 by a conduit 22. The refrigerant gas is discharged from the top of the accumulator directly into the interior of the casing 16 while the liquid refrigerant is retained therein. The reversing valve I9 is connected to the coils l0 and I l by means of conduits 23 and 24, respectively.

The reversing valve I 9 is adapted to place the compressor suction and discharge in communication with the coils l0 and II, respectively. or to reverse the connections and place them in communication with the coils II and I 0, respectively. In accordance with the present invention, the reversing valve is disposed inside the casing l6. While any cnt invention is concerned, I prefer to use the suitable construction of reversing valve may be used so far as the presthe conduits and one which is shown in Fig. 2 and which will be readily apparent from the drawing. It includes a casing 25 made in three parts and an axiallymovable valve member 26 having annular ribs or ridges 21 and 28 which extend into annular recesses 29 and 30 communicating with the conduits 23 and 24, respectively. The discharge conduit I8 communicates with the interior of the casing 25 intermediate the recesses 29 and 30, while the conduit 22 communicates with the right-hand end of the interior of the casing, and also with the left-hand end through passages formed in the valve member 26. When the valve member 26 is moved to the left so that the ribs 21 and 28 seat against the left-hand sides of the recesses 29 and 30, as shown in Fig. 2, the conduit 22 communicates with the conduit 23 and the conduit l8 communicates with the conduit 24. When the valve member 26 is moved to the right to seat the ribs 21 and 28 against the righthand sides of the recesses, the connections are reversed, the conduit 22 communicating with the conduit 24 and the conduit l8 communicating with the conduit 23. The construction of the reversing valve so far described is in accordance with the above-mentioned invention of .John G. Ritter.

In accordance with my invention, I provide common soldered joints for extending the conduits 23 and 24 through the casing l6 and into the casing 25. As shown in Fig. 2, the openings in the casing l6 through which the conduits 23 and 24 extend are of greater diameter than the conduits. The intermediate part of the casing 25 is formed with flanges 3| which encircle extend into the spaces between the conduits and the edges of the openings substantially flush with the outer surface of the adjacent portion of the casing l6, which portion is preferably substantially fiat. The solder is then applied, as shown in Fig. 2, to contact the conduit, the flange 3| and the casing I6. Accordingly, there is provided by a single soldering operation a seal between the conduit and the casing 25 and a seal between the conduit and the casing l6.

Suitable provision is made for actuating the reversing valve Hi. In accordance with a further feature of my invention, it is actuated by and in accordance with the direction of rotation of the shaft 20 of the motor-compressor unit. By using a single phase capacitor motor, the direction of rotation may be readily reversed by connecting the capacitor winding to one side or the other of the electrical supply conductors. This is illustrated in Fig. 1, wherein the double-throw switch 3| is adapted to place the circuit of the capacitor winding, which includes the capacitor 32, to either th line conductor L1 or L2. When the capacitor circuit is connected to the conductor L1, the shaft 20 rotates in clockwise direction as seen in Fig. 1, and when it is connected to the conductor L2, the shaft rotates in counterclockwise direction. A switch 33 may be provided in the line conductor L1 to interrupt the supply of current to the motor.

The mechanism for actuating the reversing valve l9 may be of any suitable form. For simplicity of illustration, I show a sleeve 34 which encircles the shaft 20 and which is dragged by the shaft when it is free to rotate. However, it is adapted to slip relative to the shaft when held against rotation. As will be noted from Fig. 1,

when the shaft 20 rotates in clockwise direction,

the sleeve 34 moves the movable valve member 26 to the left of the position shown to cause the refrigerating system to operate on the cooling cycle. When the shaft 20 rotates in counterclockwise direction, the sleeve moves the valve member 25 to the right for the heating cycle. -A screw 35 is provided to adjust the degree to which the sleeve 34 is clamped on the shaft 20, in order to adjust the degree of drag or slip.

The reversible cycle refrigerating system, which is illustrated diagrammatically, may be incorporated in any suitable form of apparatus. It is particularly suited for a self-contained air conditioning unit adapted to be mounted either in the window of a room, or a unit adapted to be placed in a room and connected to the outside with suitable ducts.

Operation Assume that it is desired to cool the enclosure served by the illustrated refrigerating system. The switch 3| is placed in the position illustrated to provide the cooling cycle, and the switch 33 is closed to connect the motor with a source of electric current. The shaft 22 rotates in clockwise direction,

moving the valve member 26 to the left to the position illustrated. The system now operates in the usual manner of a refrigerating system. Refrigerant vapor from the interior of the casing I6 is drawn through the motor and the conduit l1 to the compressor where its pressure is increased. The compressed refrigerant is conveyed through the conduit 18, the connecting passage of the reversing valve IS and the conduit 24 to the outside air coil H. The condensed refrigerant flows through the capillary tube l2 wherein its pressure is reduced. It then flows through the conditioned air coil l0, wherein it extracts heat from the air which is circu- 40 lated over the coil l0 and delivered to the enclosure, the refrigerant being vaporized by the extracted heat. The vaporized refrigerant then flows through the conduit 23, the connecting passage of the reversing valve I9, and the conduit 22 and the accumulator 23 to the interior of a casing Hi, from which it is recirculated.

To heat the enclosure, the switch 3| is moved to the lower position and the switch 33 is closed. The shaft 20 now operates in counterclockwise direction, dragging the sleeve 34 with it until the valve member 26 is moved to the right. The connections are now reversed so that the compressed gas flows through the conduit 23 to the conditioned air coil I0. As it flows through'the coil lfl, it gives up its super heat and latent heat to the air circulated over the coil and is thereby condensed. The heated air is delivered to the enclosure to maintain it at a comfortable temperature. The condensed refrigerant flows through the successive tubes to the bottom of the coil I0. from which it enters the capillary tube l2. From the latter it enters the outside air coil ll. As it flows through the latter, it absorbs heat from the outside air flowing over the coil II and is thereby vaporized. The vaporized refrigerant discharged from the upper end of the coil H, flows through the conduit 24, the connecting passage of the reversing valve 19, the conduit 22 and the accumulator 23 to the interior of the casing "5. From the latter it is recirculated through the motor, the conduit l1 and the compressor l4 to the discharge conduit H3.

The operation of the trolled thermostatically 75 this case, the switch compressor may be conby a thermostat T. In 33 ,is replaced by contacts 33a and 33b which ture rises above desired tempera ure zone.

'le I have shownmy invention in but one form, it will be obvious to those skilled in the art pended claims.

What I claim is:

1. In a reversible cycle refrigerating system for heating or cooling an enclosure, the combination of a compressor, a motor driving the compressor, a fluid-tight ond heat exchanger, respectively, for heating said second and said first heat for cooling said enclosure,

second heat exchanger, expansion means connected between said heat exchangers; and reposite directio 3. In a reversible cycle refrigerating system for heating or cooling an enclosure, the combination of a compressor, a motor driving the compressor.

a fluid-tight casing enclosing the motor and the 4. In heating heating said enclosure or to said second and said exchanger, for cooling teriorly of said fluid-tight casing for controlling of said electrically energized means.

a reversible cycle refrigerating 5. A motor compressor unit for a reversible cycle refrigerating or said motor in the opposite direction.

'6. A motor compressor cycle refrigerating l system comprising a compresreversing valve means having first and second ports and disposed within said fluid-tightcasmg second ports, respectively, or to said second and said first port, respectively, conduits connected to said first and second ports of said reversing valve means, said i asing having an opening or openings to provide communication between said conduits and said re ersing valve means, and a common soldered Joint providing a seal between casing and a seal between the conduit and reversing valve means.

EDWARD R. WOLFERT. 

